考察点：数组
public int findKthLargest(int[] nums, int k) { if (k < 1 || nums == null) { return 0; } return getKth(nums.length - k +1, nums, 0,nums.length - 1);} public int getKth(int k, int[] nums, int start, int end) { int pivot = nums[end]; int left = start; int right = end; while (true) { while (nums[left] < pivot && left < right) { left++; } while (nums[right] >= pivot && right > left) { right--; } if(left == right) { break; } swap(nums,left, right); } swap(nums, left, end); if (k == left + 1) { return pivot; } else if (k < left + 1) { return getKth(k, nums, start, left - 1); } else { return getKth(k, nums, left + 1, end); }} public void swap(int[] nums, int n1, int n2) { int tmp = nums[n1]; nums[n1] = nums[n2]; nums[n2] = tmp;}
